In the global debates on English as international lingua franca or as ‘killer language’, the adoption of English as medium of instruction in Higher Education is raising increasing concern. Plurilingualism and multilingualism are embedded in the official policies of the European Union and Council of Europe, and the Bologna Process for harmonizing Higher Education promises ‘proper provision for linguistic diversity’. But even enthusiasts acknowledge the problems of implementing such policies in the face of an inexorable increase in the use of English. This survey draws on the most recent and sometimes disparate sources in an attempt to paint a comprehensive and up-to-date picture of the spread of English-medium teaching in Europe's universities. The article sets the changes in the context of accelerating globalization and marketization, and analyses the forces which are driving the adoption of English, and some of the problems which accelerating ‘Englishization’ of European Higher Education might create.